1. Field of the Invention
The present invention relates to a developing apparatus that supplies a developer material to a developing member and an image forming apparatus that incorporates the developing apparatus.
2. Description of the Related Art
Electrophotographic image forming apparatuses including printers, copying machines, and facsimile machines use electrophotographic technology. An exposing unit illuminates the uniformly charged surface of a photoconductive drum to form an electrostatic latent image. The electrostatic latent image is developed with toner into a toner image. The toner image is then transferred onto print paper. Subsequently, the toner image on the paper is fixed into a permanent image.
If the toner in the developing apparatus has been deteriorated, a sufficient amount of the toner may not be supplied to a toner supplying roller and a developing roller reliably. Deteriorated toner causes uneven toner density in developed images or causing light or vague images to be printed. JP2002-31952A discloses a developing apparatus in which a toner supply controlling member causes toner to fall onto a contact area where a toner supplying roller and a developing roller are in contact with each other.
However, if a gap between the toner supplying roller and the developing roller is relatively large, the toner is subjected to convection in the gap so that the toner is difficult to adhere to the toner supplying roller or the toner adhering to the toner supplying roller may come off.